D. DAS, S.B. MOHAPATRA AND P. RAY
Abstract
Biosurfactants are amphiphilic compounds produced on living surfaces, mainly on surfaces of microorganisms or secreted extracellular. Different screening methods like cetyl trimethyl ammonium bromide (CTAB) assay, haemolytic assay (HA), tilted glass slide test (TGST), oil spread method (OSM), emulsification index (EI) etc. were used to assess their efficiency for bacterial biosurfactant production. Out of twenty bacterial colonies, isolated from Bhitarkanika Mangrove forest, only five were found positive for biosurfactant production like haemolysis test, oil spreading technique, lipase test, tilted glass slide test and CTAB activity. The highest emulsification index (50%) was observed by gram (+) ve isolates (BMSed II). The above five isolates were identified as Bacillus sp. (BMSed II, BBSed IV, BRSed I, BDSed II) and Pseudomonas sp. (BMSedV) based on microscopic and biochemical analysis. The study revealed that tilted glass slide test, oil spreading test, CTAB test, haemolysis test, emulsification index and lipase test are the suitable tests for primary screening of biosurfac tant producing microorganisms.